Counterweights for Manual Flying
Counterweights are the most satisfactory way of manually flying stage equipment and lighting, whether single-purchase or double-purchase. The general principles are similar for all counterweights, with a system of suspension cables and hauling ropes passing over pulleys, a barrel flying at one end, and a guided weight cradle at the other end runs in a wall frame.
Single purchase counterweights should be employed where the travel available for the weight cradle is equivalent to that required for the barrel. In the double-purchase system the weight cradle travels only half the distance of the barrel, and requires double the quantity of weights in the cradle, but it is ideal if additional wing space is required or when space on the stage wall is limited due to doorways or lack of height.
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Counterweights during installation
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Rear-guided front-loading weight cradles and wall frame
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Single-purchase, with double-purchase where less height
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Weights being stored on operators loading gallery
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Operating gallery and guarded counterweight sets
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Typical head pulleys
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A lowered counterweight barrel with lighting
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An unusual configuration of diversion pulleys!
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The flymans' eye view of couterweights in use
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Steel frame built inside an old theatre to support new kit
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| If restricted height, wall frame may extend below stage |
Labelled raised barrels with extension tubes |
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If limited height, stage floor may replace operating gallery
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Load test, showing barrel termination and extension tube
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